Modern heat treatment

[SkagSig40]

Is there a company or person that can do a full modern heat treat on a Khukuri? I know the Kami's are very good but I wonder if the blade would benefit from a modern fully controlled heat treamtent and temper.

What do you think?

 

[Cpl Punishment]

There's plenty of places that do heat treats.
Just keep in mind a couple of things.

1.) The reason behind a differential heat treat is to provide a hard edge that will hold up with a softer spine so the blade won't break. A lot of "modern" shops still use this type of heat treat on larger blades.

2.) The heat treat facility will want to know the exact type of metal used. "Mercedes truck leaf spring" WILL NOT be acceptable. They'll want the actual classification of the steel (and I don't know if Mercedes has changed their steel used over the decades).

 

[cybrok]

Modern HT is better for high quantities, but for a handmade differentially treated blade, like a khukuri or a Katana, I prefer good old methods teached by masters to their apprentice.

 

[SkagSig40]

Thanks guys. I hve bought over 50 HI's over the years and I test all of them with a file. Bill taught me how to do this. Most khukuries are pretty close to each other in edge hardness. A few the file shows are softer along the edge and a few harder but most are close to each other. I wish I had a Rockwell tester to see exactly how hard each blade is.
I was wondering what a 58rc blade would be like harden all the way through. There are lots of big knives that have a high hardness all the way through that are still flexable and do not break. The Cold Steel Trailmaster and their Khukuries come to mind allong with some of Bussie's large knives. I would bet a HI khuk would perform well hardened allthat way to 58rc C scale.
What do you guys think?

 

[sams]

I don't think a chopping tool should be harden / tempered all the way through. I come from the old school, if it works for a few hundred years, leave it be, the way the kamis do it.

 

[Yvsa]

Chris I think 58 Rc would be too hard for a kukri hardened all the way through. You could probably get away with 54 - 55 Rc but I wouldn't even want that even though some knives are only 52 Rc, the Okapi African folders IIRC.
The full hard modern knives like the Trailmaster aren't spring steel and therefore will handle the full hardness although a person would be better served if its spine were softer like a kukri and what I consider most really good Bowies.
And with Busse you're comparing Washington Delicious Apples with Brazilian Mangoes with their INFI.
However with all that said I personally think that a person would be better served with the edge hardened from the kaudi (cho) too the tip instead of as they are. Or at least quite a lot harder in those areas than they are.
I understand why they're made that way and especially for use in Nepal and other countries with similar fauna and terrain.

And how have you and your beautiful bride been the last while? You haven't been around in a coon's age it seems!

 

[cybrok]

I should try to cut a khuk and make some metallographies. Could be cool

 

[SkagSig40]

Chris I think 58 Rc would be too hard for a kukri hardened all the way through. You could probably get away with 54 - 55 Rc but I wouldn't even want that even though some knives are only 52 Rc, the Okapi African folders IIRC.
The full hard modern knives like the Trailmaster aren't spring steel and therefore will handle the full hardness although a person would be better served if its spine were softer like a kukri and what I consider most really good Bowies.
And with Busse you're comparing Washington Delicious Apples with Brazilian Mangoes with their INFI.
However with all that said I personally think that a person would be better served with the edge hardened from the kaudi (cho) too the tip instead of as they are. Or at least quite a lot harder in those areas than they are.
I understand why they're made that way and especially for use in Nepal and other countries with similar fauna and terrain.

And how have you and your beautiful bride been the last while? You haven't been around in a coon's age it seems!

Hi Yvsa,
Good to see you too! With all my other hobbies and work and all I just don't get here much anymore. Been buying a lot firearms lately. Now I'm getting back to Khuks! Just bough a Tin Chirra that other day from Yangdu. Chamaine is really good and is finally out of school! She acctually asked me if you got off all those meds you were on and feeling better?

I agree with the idea that a fully harden blade may not be the best think for a chopper. I was wondering though would a nice draw temper even out the steel and get all the stress areas and internal micro cracks out of the steel from when it was shocked when the water hit it from the Kami?

 

[Kismet]

Hey Chris...

I always wished the kamis would have hardened the SARGE knives all the way through. For a woods knife/sheath knife, seems most appropriate. Don't think it happened though. Wonder if the the R6 R7 mods are hardened throughout.

Nice to see you posting.:thumbup:

 

[Steely_Gunz]

Hey Chris...

I always wished the kamis would have hardened the SARGE knives all the way through. For a woods knife/sheath knife, seems most appropriate. Don't think it happened though. Wonder if the the R6 R7 mods are hardened throughout.

Nice to see you posting.:thumbup:

I don't think that the R-6 is hardened all the way through. At least mine isn't. The tip and belly seem to be pretty hard, but the spine feels softer when i push a file along it. I don't think that the sharpened clip is as hard as the edge either. I really ought to etch mine to find out for sure. It needs a good scrubbing anyway.

 

[SkagSig40]

I don't think that the R-6 is hardened all the way through. At least mine isn't. The tip and belly seem to be pretty hard, but the spine feels softer when i push a file along it. I don't think that the sharpened clip is as hard as the edge either. I really ought to etch mine to find out for sure. It needs a good scrubbing anyway.

How do you etch a blade again? Is it time consuming?

 

[Yvsa]

Hi Yvsa,
Good to see you too!
Chamaine is really good and is finally out of school! She acctually asked me if you got off all those meds you were on and feeling better?

I was wondering though would a nice draw temper even out the steel and get all the stress areas and internal micro cracks out of the steel from when it was shocked when the water hit it from the Kami?

Thanks Chris and thank Chamaine as well, sorry to say I am now up to number seven with the amount of back/neck surgeries and so far still going strong with the meds.

As far as the kamis shocking the steel when they pour the water on for hardening I don't think it is "shocked" all that much as I understand they use very hot or boiling water for hardening the edges.
We have had quite a few discussions in the distant past about how the kukris are hardened and what happens seeing as how the kukri isn't actually tempered by "drawing" the hardened steel in an oven.
The consensus was that the still very hot steel that remains in the body of the kukri, "draws" the hardness of the edge back from the very brittle state it would otherwise remain in.
Uncle Bill once told us that Bura told him the water was poured along the edge seven times and that the kami had to watch the colors change so that the edge would be as it should be when finished.
It wouldn't hurt to put a kukri blade in the oven and "draw" it back but I personally wouldn't bother.
If a kukri doesn't fail when you do the initial proof testing, providing you proof it properly, it's doubtful it ever will.

Have you had some kind of experience with a kukri that would lead you to ask/wonder about this?

 

[SkagSig40]

Thanks Chris and thank Chamaine as well, sorry to say I am now up to number seven with the amount of back/neck surgeries and so far still going strong with the meds.

As far as the kamis shocking the steel when they pour the water on for hardening I don't think it is "shocked" all that much as I understand they use very hot or boiling water for hardening the edges.
We have had quite a few discussions in the distant past about how the kukris are hardened and what happens seeing as how the kukri isn't actually tempered by "drawing" the hardened steel in an oven.
The consensus was that the still very hot steel that remains in the body of the kukri, "draws" the hardness of the edge back from the very brittle state it would otherwise remain in.
Uncle Bill once told us that Bura told him the water was poured along the edge seven times and that the kami had to watch the colors change so that the edge would be as it should be when finished.
It wouldn't hurt to put a kukri blade in the oven and "draw" it back but I personally wouldn't bother.
If a kukri doesn't fail when you do the initial proof testing, providing you proof it properly, it's doubtful it ever will.

Have you had some kind of experience with a kukri that would lead you to ask/wonder about this?

Thanks Yvsa and I'm sorry to hear you are still batteling for good health....you hang in there.

I do not use most of my khuks these days but I'm starting to "proof" them now. How do you test/proof yours? I will follow your advice on this. Thank you!

 

[Daniel Koster]

Any knifemaker doing the "torch draw" heat-treat method ought to be able to heat-treat a kukri blade. Just need a quench tank long enough.

I have the tank, but use a furnace and my furnace is not long enough.

You might ask Ray Kirk if he would be willing to do it. He does a great heat-treat on 5160 (which is closest to what the spring steel seems to be).

 

[Yvsa]

You might ask Ray Kirk if he would be willing to do it. He does a great heat-treat on 5160 (which is closest to what the spring steel seems to be).

Yup, Ray could definitely do it!!!! It's been a coon's age since I've seen or talked to Ray but I've been keeping up with him the best I can in any knife news. Ray definitely does the Cherokee Nation Oklahoma up proud.:thumbup:

Chris just follow the directions that Uncle Bill set up so long ago.
Uncle Bill had a pic he showed of one of those great big wood cable/wire spools where he had an HI khukuri braced in its center hole and was leaning his weight on it. Uncle Bill also said to beat the living hell out of the khuk by whacking it as hard as possible several times sideways on both sides and then do the same with the spine.
And then of course do some heavy duty chopping with it on well seasoned hardwood such as Oak, Hickory, Ash, and the like.
Colorado has a few native hardwoods that would be suitable I'm sure if you can get in the backwoods where it's legal to cut downfall.
Otherwise you may have to find some oak flooring or such.
Another great test if the edge isn't too thin is to chop and then twist at the bottom of the cut, puts one helluva strain on any knife and I chipped a good sized chunk out of a full sized Ganga Ram's edge by doing same in some extremely hard Blackjack Oak several years ago. That was a case of being foolish because I knew better but went ahead and done it anyway.
I ground out the chip and re-profiled the edge and it's still going strong!!!!:thumbup: